cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A368250 Decimal expansion of Sum_{k>=2} (zeta(k)/zeta(2*k) - 1).

Original entry on oeis.org

8, 4, 8, 6, 3, 3, 8, 6, 7, 9, 6, 4, 8, 8, 3, 6, 3, 2, 6, 8, 4, 9, 0, 0, 1, 2, 0, 9, 0, 4, 3, 0, 4, 6, 2, 9, 6, 0, 0, 1, 6, 6, 4, 4, 6, 8, 8, 1, 7, 5, 5, 1, 7, 1, 6, 7, 9, 6, 2, 0, 3, 0, 9, 0, 0, 3, 6, 5, 4, 2, 2, 1, 3, 7, 1, 3, 0, 2, 1, 2, 9, 1, 8, 8, 6, 6, 3, 4, 8, 1, 0, 1, 1, 5, 3, 7, 0, 2, 0, 6, 3, 4, 4, 3, 7
Offset: 0

Views

Author

Amiram Eldar, Dec 19 2023

Keywords

Examples

			0.84863386796488363268490012090430462960016644688175...
		

Crossrefs

Programs

  • Maple
    evalf(sum(Zeta(k)/Zeta(2*k) - 1, k = 2 .. infinity), 120);
  • PARI
    sumpos(k=2, zeta(k)/zeta(2*k) - 1)

Formula

Equals Sum_{k>=2} mu(k)^2/(k*(k-1)) = Sum_{k>=2} 1/A368249(k).
Equals Sum_{k>=1} 1/A072777(k).
Equals lim_{m->oo} (1/m) * Sum_{k=1..m} A368251(k).